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प्रश्न
Ice kept in a beaker, slowly melts and turns into water. The water in the beaker on solidification is freezing turns back to ice. Give four reasons why the change from ice to water and water back to ice is considered a physical change.
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उत्तर
Both changes are physical changes since
- The change is – temporary
- It is a reversible change
(heating and cooling reverse the change)
heating of ice – turns it into the water,
cooling of water – turns it back into ice - No new products are formed since both ice and water are chemical – ‘H20’
- Properties of the original substance are not altered.
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संबंधित प्रश्न
When a candle burns, both physical and chemical changes take place. Identify these changes. Give another example of a familiar process in which both the chemical and physical changes take place.
Tick the most appropriate answer.
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- change in size.
- change in molecular composition.
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What will you take into account while identifying the following?
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